Virtually all buildings and enclosures where human activity takes place require venting of one type of another. The type of venting device employed will depend on the kind of enclosure to be vented. For example, bathrooms containing showers typically have active vents with fans to vent steam to the outdoors. Kitchens, particularly in restaurants and hotels, similarly have powered vents for removing smoke and steam to the outdoors.
Other types of enclosures, such as attics and yard sheds, do not require active venting. However, such enclosures do typically require a passive vent to allow for air flow from the enclosure to the atmosphere. Such venting is required, for example, to prevent a buildup of moisture in the enclosure. Passive vents do not include a mechanism for forcing air out of the enclosure. Rather, they simply include a vent structure in the form of an air conduit which allows air flow. Passive vents are well-known and have been extensively used in the past. Although typically formed of metal, good results have been achieved more recently with plastic vents.
In addition to the venting of air from attic spaces and sheds, there are other needs for building enclosures, such as the need for light. In some cases, wiring is provided for electric lights, but spaces such as attics and sheds are typically left unwired, thus creating a need for the use of flashlights and the like.
There have been attempts in the past to provide both functions through a single structure. For example, U.S. Pat. No. 5,561,952 teaches a static roof vent comprising a base/flange containing an air conduit, and a hood. The hood includes a translucent oriel located above the air conduit. However, this device is difficult and expensive to manufacture, in that the central oriel is made from an expensive clear material which must be inserted into specially designed opaque mounts which in turn are attached to the roof.
U.S. Pat. No. 5,435,780 discloses a ventilated skylight having a light transmissive dome. The dome is supported by a support ring which is initially provided in two halves and must be welded together for use. The support ring is then installed on a soaker tray which is in turn is attached to the roof. Separate ventilation tabs are inserted into the underside of the light transmissible dome to provide ventilation. However, this device is complicated and expensive to assemble, as it requires many different parts for operation, some of which must be welded. It is also expensive to manufacture because of the large number of parts.
U.S. Pat. No. 3,934,383 discloses a roof vent for use in vans and the like. The roof vent cap is formed of a light-transmissive plastic resin. The cap is opened by turning a crank, and the cap opens at an angle. When the cap is closed, there is no venting. However, this device is expensive and complex to manufacture, requiring a complex cranking and opening assembly. Furthermore, light transmissive plastic resins typically degrade from exposure to ultraviolet light in the outdoors, taking on an unattractive yellow appearance. This patent does not address this yellowing problem.
U.S. Pat. No. 4,730,552 discloses a ventilating skylight. The device includes a housing having an opaque top wall. The housing includes front and rear openings through which sunlight may pass when the door to those openings are open. There is further a transparent dividing wall below the openings and parallel to the top wall. The transparent dividing wall has an air flow passage at its centre. However, this device is difficult and expensive to manufacture, assemble and install. It is fabricated from a number of different materials and consists of a large number of pieces, some of which are attached to one another by hinges, thus increasing the complexity of manufacture and assembly.